ELECTRONIC SIGNATURE PROXY SERVER, ELECTRONIC SIGNATURE PROXY SYSTEM, AND ELECTRONIC SIGNATURE PROXY METHOD

摘要

PROBLEM TO BE SOLVED: To provide an electronic signature technique which properly performs proxy electronic signature on behalf of a user terminal.SOLUTION: An electronic signature proxy server comprises: means for receiving, from a user terminal of a user, secondary protection certificate data which is acquired by performing encryption of a predetermined encryption method on primary protection certificate data including an electronic certificate protected by personal identification data of the user and a secret key that are issued by an authentication station; means for acquiring the primary protection certificate data by decrypting the secondary protection certificate data; means for holding the acquired primary protection certificate data; means for transmitting screen data for requiring the user to input the personal identification data; means for removing protection by the personal identification data from the held primary protection certificate data by using the personal identification data input via the input screen; and means for attaching an electronic signature to target data by using the secret key acquired by the protection removal processing.